My answer to On a neurological level, what allows dementia sufferers to retain musical memory?

Answer by Connie b. Dellobuono:

Sounds, such as music and noise, are capable of reliably affecting individuals’ moods and emotions, possibly by regulating brain dopamine, a neurotransmitter strongly involved in emotional behavior and mood regulation.

In parkinson, there is loss of dopamine-secreting neurons in an area of the midbrain

In Dementia, the chemical-brain pathway is different than Parkinson though they intersect at some point. Memory related health issues are prominent.

Music is affecting our emotion and mood regulation (pituitary gland).

On a neurological level, what allows dementia sufferers to retain musical memory?